#define _CRT_SECURE_NO_WARNINGS
#include<stdio.h>
int main()
{
	int b = 0;
	int a = 0;
	int sum = 0;
	for (b = 1; b <= 100; b++)
	{
		int num = b;
		do
		{
			a = num % 10;
			num = num / 10;
			if (a == 9)
			{
				sum++;
				break;
			}
		} while (num != 0);
	}
	printf("%d", sum);
	return 0;
}
